5-Minute Abs (Proven in a Lab!)

Lie faceup with right leg extended, left knee bent with left foot flat, left arm above chest and right hand gripping left arm, elbow out. Engage abs and slowly roll up (as shown). Return to start. Do 12 reps; repeat on opposite side.

Exercise physiologist Michele Olson has dedicated a chunk of her career to discovering the fastest, smartest way to firm your abs. Here, an exclusive routine based on her latest findings. The research will transform your gut.